Research has demonstrated specific impairments in infants of depressed mothers, and in the interactions between these infants and their mothers. These impairments include developmental delay, deficits in infant affective and cognitive behavior, poor mother-child attunement, and psychophysiological abnormalities. The participants for this project will be drawn from males and females enrolled in the Oregon Adolescent Depression Project. Females from the sample who become pregnant during a three year recruitment period (n-126). These participants, their partners, and their infants will be assessed on four occasions over the first two years of the child's life. Assessments will include current and past psychopathology amongst the mothers and fathers, marital functioning and familial context, parenting behaviors, parental perceptions of the infant, and observational data pertaining to infant development. The infant will also be observed interacting with each parent in order to examine both parental and infant affect and responsiveness. The three specific aims are to examine: (1) the effect of different aspects of parental depression, including family and personal history of depression on the developmental of infants, (2) the specificity of the abovementioned impairments in infant development of depression, and (3) the role of fathers and the marital relationship in the development of impairments in infants. The results of this study will allow assessment of how history of depression (including family history) influences the development of infants, either through its influence on parental depression in the post-partum period, or as a trait marker that adversely affects parenting independent of current psychopathology. The second aim will be addressed by the inclusion of mothers and fathers with histories of psychiatric disorders other than depression, and the assessment of a wide variety of psychopathology in both. The third aim will be addressed by examination of levels of depression and other psychopathology in fathers, the marital relationship, and observation of their interactions with their child. The public health benefits of this study include knowledge about risk factors that can be used to identify children who are at especially elevated risk, and about specific parental behaviors which are involved in the transmission of risks. This information is important for the design of preventative interventions intended to reduce the deleterious effects of parental depression on children.